1. Field of Invention
The invention is related to a device for mixing and supplying solutions or live food cultures in aquariums such as, for example, reef aquariums and other aquariums. More particularly, the invention is related to a motorless reactor for an aquarium system to automate the process of replenishing calcium and alkalinity, pH maintenance, and/or live food culture and delivery.
2. Related Art
In nature, the limitless supply of seawater that bathes coral reefs provides the minerals utilized by reef creatures to build their skeletons. Hard corals, coralline algae, and other calcifying algae and invertebrates, which are the building blocks of the coral reef, demand large amounts of calcium and carbonates to build their skeletons.
In reef aquariums that are designed to grow live corals in a closed body of recirculating seawater, the addition of dissolved calcium and carbonates is essential to accommodate the needs of the calcifying corals, other invertebrates, and algae that build calcareous skeletons, shells, and cementing crusts from the calcium and bicarbonate ions they extract from the alkaline seawater solution they live in. It is common practice to daily replace evaporated water by topping off the aquarium with a solution of freshly mixed calcium hydroxide in freshwater, because it is a source of calcium, and because it boosts carbonate alkalinity since the addition of the highly alkaline solution of calcium hydroxide causes additional carbon dioxide to dissolve in the aquarium water. The solution of calcium hydroxide in freshwater is known as “limewater,” but most commonly referred to with the German translation, “kalkwasser.”
Many systems for dosing kalkwasser exist (See Delbeek & Sprung, The Reef Aquarium, Vol. 3, 2005, incorporated herein by reference), but the most efficient methods utilize a chamber called a reactor where the calcium hydroxide powder is mixed with freshwater prior to being added to the aquarium. Aquarists can accomplish this manually by putting the calcium hydroxide into a small jug of water and shaking it, allowing the un-dissolved calcium hydroxide to settle and decanting or drip-feeding the saturated clear solution to the aquarium. The advantage of using a reactor is that a saturated solution can be created automatically for several days, involving less work by the aquarist. Excess calcium hydroxide is added to the reactor, and it sinks to the bottom because it has a low solubility. A stirring device mixes it with water in the reactor, creating a solution that is saturated or supersaturated. Pure freshwater used as top-off water for the aquarium is added by a dosing pump to the reactor, and the saturated solution overflows from the reactor, being conducted by gravity into the aquarium. The mixing is usually done at timed intervals, allowing the un-dissolved calcium hydroxide powder to settle so that only clear saturated kalkwasser is dosed to the aquarium. It is also possible to dose milky, unsettled kalkwasser, but this is potentially risky as the chance of overdose is higher. If the water feed passes through the un-dissolved calcium hydroxide from the bottom of the reactor upward, a gentle mixing can be achieved that creates saturated kalkwasser without the need for timed settling.
Previous reactors generally have a high cost due to additional motors and/or motorized parts required for mixing that are prone to failure and need regular maintenance. In designs where the motors or pumps are directly exposed to limewater, extra careful maintenance is required to remove the deposits of calcium carbonate that rapidly form on the magnetized and moving parts.